Embodiments of the invention relate to a device for insertion into a rotor of a centrifuge such as, for example, on a standard laboratory centrifuge. Further embodiments relate to a method for coupling cavities fluidically. Further embodiments refer to a centrifuge.
The implementation of (bio)chemical processes needs the handling of liquids. On the one hand, this occurs manually with the assistance of pipettes, reaction vessels and further auxiliary process means such as, for example, columns or magnetic particles and laboratory equipment and, on the other hand, automatically relying on pipetting robots or other special instruments.
So-called lab-on-a-chip (LOC; i.e., laboratories on a micro-component) systems seek to automate individual process steps, simplify the handling of process liquids and target the development of cost-effective, compact systems. The main objective of lab-on-a-chip systems is miniaturization.
For the most part, lab-on-a-chip systems include an arrangement of two main components. Typical lab-on-a-chip systems therein have a passive fluidic disposable cartridge (also referred to as test carrier) that contains channels, reaction chambers as well as pre-stored reagents and, moreover, an active instrument that contains actuator components as well as detection and control units. This active instrument is typically adjusted to the requirements of the fluidics cartridge. Therefore, such instruments are associated with high costs in terms of development, manufacturing and acquisition. This is the reason why efforts are underway to automate (bio)chemical processes that need only minimal instrumentation or none at all. Examples for this are testing strips (also referred to as a lateral flow test). Such approaches, however, often suffer from the disadvantage that processes that are expediently automated can only comprise few steps; moreover, their sensitivity is limited. For many (bio)chemical processes (for example, synthesis, analysis and filtration), centrifuging is an essential component of processing. A centrifugal force that is generated by centrifuging action therein is used either for the transportation of liquids from a processing step that is radially further to the inside to a processing step that is radially located at the outside, or for purposes of material separation on the basis of varying densities.
Therefore, centrifuges are an essential aspect in any laboratory that handles (bio)chemical processes.
To be detailed below are automated systems that allow for handling several process steps in the context of (bio)chemical processes in an automated fashion.
Pipetting robots with integrated centrifuge have already been known in the art. Systems of this type have a pipetting robot with a pick-up device and an integrated centrifuge allowing, for example, for the automated filtration of DNA, RNA and proteins. In certain systems therein, it is possible to purify up to twelve samples per run.
A disadvantage of such automated system for customers are the high costs associated with the acquisition of special equipment, extra space requirements inside the laboratory and the needed familiarization period for qualified personnel.
Other special instruments utilize a non-centrifugal automation alternative for handling liquids. With such so-called fluidically integrated systems, it is possible to separate (nucleic acid extraction) and analyze samples (for example, for a so-called PCR in real time). To implement the tests, special containers are needed that are adjusted to the fluidically integrated system. Said containers and/or reaction vessels consist of a flexible hose that is separated by septa. The needed reagents are pre-stored inside the compartments that are thus created by the septa. Handling of the liquids takes place by means of pestles pressing against the hose thereby functioning, on the one hand, as a valve and, on the other hand, as a pump.
Using this automated system, it is possible to automate various (bio)chemical processes; however, once again, acquisition of specialized and expensive equipment is needed. Therefore, this system has the same disadvantages as the system mentioned previously.
Moreover, so-called special centrifuges for the processing of liquids have been in existence.
Document U.S. Pat. No. 4,190,530 (also published as DE 2912676 A1) discloses a specially developed centrifuge having different collecting receptacles that are disposed in a radial arrangement. The collecting receptacles therein are disposed at different spacings in relation to an axis of rotation of a rotor of the centrifuge in swing-out cup holders. The centrifuge as shown in the specification thereby allows for processing multiple fluids via different paths from a location that is in closer proximity relative to the axis of relation to a location that is at a greater distance relative to the axis of rotation. A fluid therein flows through a separation column into a first radially inside-located collecting receptacle. Located at the radially outside location are multiple collecting receptacles into which the fluid, having flowed over the separation column, can flow. By means of acceleration forces, the fluid is guided to the outside via different paths. This allows the fluid to reach different collecting receptacles. Using this system, beginning with a starting cavity at the radially inner location, different fluidic paths in the centrifuge can be embodied. In particular, using valves and lines inside the centrifuge as well as nozzles, the fluid is brought into the radially inner collecting receptacle. A disadvantage of the apparatus is that fluids of different starting cavities are not guided via the same path. Moreover, the equipment needs a special design and manufacture, thus resulting in high costs.
Document U.S. Pat. No. 5,045,047 discloses a centrifuge apparatus having a rotor with an inner and an outer ring. So-called inner containers are disposed on the inner ring, and so-called outer containers are disposed on the outer ring. In addition, the centrifuge apparatus that is disclosed in the specification includes a mechanism for preventing any radial alignment of the inner containers that is generated due to the centrifugal force. This allows for a partial alignment of the inner containers with the outer containers, whereby a fluid from an inner container is able to flow, due to the centrifugal force generated by a rotation of the rotor of the centrifuge apparatus, into an associated outer container. The specification describes this state as the aligned state. In a non-aligned state, meaning when the inner container are held such as prevent them to from being able to radially align themselves, it is possible to empty the inner containers. A disadvantage of this disclosed centrifuge apparatus is the fact that fluids from different inner containers cannot be routed into a common outer container. It is especially disadvantageous that the centrifuge apparatus, as described previously, is a piece of specialized equipment with only a limited range of applications and associated very high costs.
Document U.S. Pat. No. 5,087,369 (also published as DE 68923835 T2) discloses a method for the separation and recovery of proteins that are present inside liquids, specifically using a rotary column. Based on the rotation of the column, the fluid is circulated from an inner cylinder into an outer cylinder chamber. Again, it is disadvantageous that the fluids from different starting cavities cannot be routed into a common end cavity.
Consequently, automated systems suffer from the substantial disadvantage, in particular, that they are associated with high additional fixed costs because they rely on the purchase of special equipment. As a result, the market launch of such systems is rendered more difficult.
An alternate solution to the automated handling of liquids for the implementation of chemical and (bio)chemical processes is the manual handling of the liquids. Disadvantages associated with any manual handling are the many needed individual operating steps, such as, for example, for DNA extractions, that are to be carried out by especially trained personnel in extremely time-consuming process steps. Furthermore, there is a risk of cross contamination of the handled liquids.